Erdheim Chester Disease

A lot of times when you read a requisition, you come across a lot of diseases, syndromes and terms, especially acronyms, that medical personnel use to which you have no clue what they mean sometimes.  If it piques your interest you would look them up and if it is really pertinent to the case you would pay attention to what is written.

Well reading Erdheim Chester disease on the requisition, I really did not give a second thought (just another disease process), until I saw this.

Fig. 1  Total body bone scan of a patient with Erdheim Chester disease.  The patient had complained of localized pain in the femurs.

Fig. 2  Additional images of the arms, for completeness. 

Fig. 3 Additional images of arms to document both dorsal and ventral views... I know, I know... I didn't label them, and the fingers were cut off on the view, but they didn't really involve in completing the whole case.

So what is Erdheim Chester Disease (ECD)?  Click on the link and find out a little more, but what is interesting is that pathologists do not know how to classify this disease because it is so rare.  The bottom line is, it is a disease in which there is an accumulation of histiocytes depositing themselves into loose connective tissue.  It eventually causes thickening and progresses into dense fibrotic tissue over time.  The symptoms tend to be variable, but the one presented in this case was discomfort in the thighs and femurs, fatigue and intermittent back pain. We performed a flow and blood pool sequence of the lower body and there was a marked increase in perfusion in the blood flow and blood pool in the distal femurs*.

Fig. 3  Blood pool image after the injection of Tc99m-MDP.  The distal femurs demonstrate an increased perfusion.

The patient overall seemed healthy, when interviewed during the examination, except for the minor complaints mentioned above.  The images were checked with the radiologist upon completion of the bone scan and was released.  

So at the end of the day the lesson learned is, not to dismiss diseases, syndromes or terms so readily because it may provide an opportunity to learn.

*Note:  When we performed the total body bone scan we saw what was presented and then went back to review the flow and blood pool study more closely.